The Muffler,exhaust, cataloged under National Stock Number 2990-01-164-0120, is classified within Federal Supply Class 2990 (Miscellaneous Engine Accessories, Nonaircraft) of the Engine Accessories group. Government technical data includes 12 specifications, cited from the U.S. Government catalog. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 2990-01-164-0120 |
| Item Name | Muffler,exhaust |
| FSC / FSG | 2990 / 29 — Miscellaneous Engine Accessories, Nonaircraft |
| Status | ACTIVE |
| Operating Position | UNIVERSAL |
| Inlet Outside Diameter | 4.000 INCHES NOMINAL SINGLE INLET IN |
| Inlet Location | CENTRALLY LOCATED IN END SECTION OF BODY |
| Design Type | DRY |
| Overall Diameter | 9.000 INCHES NOMINAL IN |
| Outlet Inside Diameter | 4.000 INCHES NOMINAL FIRST OUTLET IN |
| Inlet Connection Type | UNTHREADED SINGLE INLET |
| Body Shape | ROUND |
| Surface Treatment | ALUMINUM |
| Material | STEEL LOCATION NOT OTHERWISE SPECIFIED |
| Outlet Connection Type | UNTHREADED FIRST OUTLET |
| Outlet Location | CENTRALLY LOCATED IN END SECTION OF BODY |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 90007177 | 3/2 Design control — primary reference U.S. Government activity |
| 9XD407AL | 5/9 Secondary reference Riker Products |
| 90002309 | 5/9 Secondary reference U.S. Government activity |
NSN 2990-01-164-0120 is a Muffler,exhaust, classified under FSC 2990, Miscellaneous Engine Accessories, Nonaircraft. Status: active.
Key specifications for 2990-01-164-0120: Operating Position: UNIVERSAL; Inlet Outside Diameter: 4.000 INCHES NOMINAL SINGLE INLET IN; Inlet Location: CENTRALLY LOCATED IN END SECTION OF BODY; Design Type: DRY. 12 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.